Type-writing machine.



No. 673,426. Patented May 7, I91. J. H. DYETT. 6

TYPE WRITING MACHJNE.

(Application filed m 19, 190m (No Model.)

ATTORNEY.

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WITNESSES:

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UNITED STATES PATENT OFFICE.

JAMES H. DYETT, OF BROOKLYN, NEW YORK,-ASSIGNOR TOWAGNER TYPEWRITER COMPANY, OF NEW YORK, N. Y.

TYPE-WRITING MACHINE.

SPECIFICATION forming part of Letters Patent No. 673,426, dated May 7, 1901.

Application filed May 19, 1900. Serial No. 17,191. (No model.)

To aZZ whom it may concern.-

Be it known that I, JAMES H. DYETT, a citizen of the United States of America, residing at the borough of Brooklyn, New York city, in the county of Kings and State of New York, have invented certain new and useful Improvements in Type-Writing Machines, of which the following is a specification.

My invention has reference to improvements in type-writing machines, and particularly to what is commonly known as the escapement--that is, the means whereby the step-by-step motion of the carriage is accomplished upon the depression and subsequent release of any of the finger-keys or of the space-bar.

The object of my present invention is to obtain a lighter and more rapid action of the machine and to simplify the construction of the escapement.

To this end my invention consists, essentially, in providing the face of each tooth of the space-rack with a portion extending substantially at right angles to the longitudinal axis of the space-rack and with a second portion inclined or oblique to said axis and combining with said rack a pivoted stepping-dog adapted to engage with the straight portions of the rack and a rigid space-cam adapted to engage with the oblique portions of the teeth, said dog and cam being secured to the spacing-rocker and the oblique portions of the rack-teeth and of the space-cam cooperating to force the rocker to its normal position.

The nature of my invention will best be understood when described in connection with the accompanying drawings, in which- Figure 1 represents a plan or top view of a type writing machine embodying my improved escapement, part of the machine being broken away. Fig. 2 is a vertical section on the line 2 2, Fig. 1. Fig. 3 is a plan or top view of the stepping-dog. Fig. 4is a sectional plan view of the same. Fig. 5 is alongitudinal section of thestepping-dog 011 an enlarged scale. Figs. 6 and 7 are sectional diagrams illustrating the operation of the escapemeut.

Similar letters and numerals of reference designate corresponding parts throughout the several views of the drawings.

Referring at present to Figs. 1 and 2 of the drawings, the letter a, designates the rocker of a type-writing machine, which, as usual, is mounted in suitable brackets at its opposite ends and is provided with arms I) b, to which are attached the upper ends of the connecting-wires c of the universal bar d, upon which the several key-levers e and also the space-bar levers f rest, so that when one of the finger-keys or the space-bar his depressed the rocker is oscillated or turned in one direction and when the key or bar is released the rocker is returned to its normal position. To the platen-carriage 2', which is guided to move in a straight line, as usual, is affixed at space-rack 1, provided alongits outer edge with a rack 2,having teeth ofa novel construction. The upper portion 3 of the face of each tooth extends substantially at right angles to the longitudinal axis of the space-rack 1, while the lower portion 4 extends obliquely or at an inclination to said axis. (See Figs. 6 and 7.) The first part I shall hereinafter call the straight portion and the second part the oblique portion of the tooth. The rocker a is provided with a bracket 5, rigidly secured thereto and participating in its oscillations, and the movement of the bracket is limited in both directions by a suitable stop, as j, acting on the tail portion of the same. Upon the inner end of the bracket 5 is mounted the stepping-dog 6, the same being pivoted to the bracket at 7, so that it can swing in a horizontal plane between two stops 9 and 10 on the bracket. Said stepping-dog is provided with'a spring-pressed pivoted nose 11 to permit man ual return of the carriage. The stepping-dog 6 is subjected to the action of a spring 8, tending to force said dog against the stop 9-that is to say, in a direction opposite to the longitudinal movement of the spacerack 1 in feeding the carriage t. The stepping-dog 6 is thrown against the second stop 10 by the engagement of the teeth of the space-rack with its nose 1l,in view of the fact that the carriage is under the tension of the usual spring feeding the same forward. The stops 9 and 10 may be in the form of adjusting-screws, so as to be able to nicely adjust the swing or throw of the stepping-dog 11. They are so adjusted that the space-arm and stepping-dog can swing sufficiently to permit the stepping-dog to move through one tooth at each operation. The stepping-dog is pivoted to the arm 6 to swing horizontally and is provided with a straight-face tooth adapted to engage with the straight portions 3 of the teeth on the space-rack, and it is subjected to the, action of the spring 12, which permits the said stepping-dog to turn in a direction opposite to the longitudinal motion of the space-rack, while it is prevented from turning in the other direction by a suitable stop, as 13, formed by a shoulder on the arm 6. Beneath the stepping-dog and secured to or forming part of the bracket 5 of the rocker a is situated aspace-cam 14, which participates in the oscillatory movements of the rocker. The contact-face 15 of the space-cam is inclined substantially the same as the oblique portions 4 of the space-rack teeth.

Normally the parts of the escapement are in the position shown in Fig. 6, the rack and carriage being prevented from moving by the engagement of the stepping-dog 11 with the rack. When a finger-key or the space bar is depressed, the space-cam 14, which is normally out of contact with the teeth of the space-rack 1, is lifted in virtue of the upward swing of the bracket 5, while at the same time the stepping-dog is lifted to clear the straight portion 3 of the respective tooth with which it was in engagement when the machine was at rest, and theparts then assume the position shown in Fig. 7. During this upward movement of the space-cam and stepping-dog the space-rack may have advanced slightly or not, according to the original relative positions of the parts. As soon as the nose ll clears the respective tooth the stepping-dog is thrown forward to bring the latter to a position where it will be engaged by the straight portion of the next succeeding tooth when the bracket is turned downwardly. When the finger-key or the space-bar is released,-the space-bar is moved forward under the tension of the usual band or mainspring, and the force which the oblique portion 4 of the respective tooth on the space-rack exerts on the oblique portion 15 of the space-cam forces said space-cam downwardly, together with the bracket to which it is attached. The rack in moving forward engages the stepping dog with the straight portion of the succeeding tooth and turns the same until it strikes the stop 10, whereupon the rack and carriage are stopped, the carriage having advanced through the space of one tooth.

It will be readily understood that in view of the oblique portions on the teeth and on the space-cam I can avoid the usual spring attached to the bracket 5 for turning the rocker ato its normal position, and consequently obtain a much lighter, smoother, and more rapid action.

It is of course to be understood that I do.

not wish to restrict myself to the exact details of construction herein described, as it is evident that modifications could be made without departing from the spirit of my invention, nor do I wish to restrict myself to the application of the escapement to any particular type of writing-machine.

What I claim as new is-- 1. An escapement for typewriting machines consisting of a space-rack provided with teeth each having a straight and an oblique portion on its face, a bracket mounted to rock transversely to the space-rack, astepping-dog movably carried by said bracket and adapted to engage the straight portions of the teeth, and a space-cam also mounted on said bracket and provided with an oblique portion adapted to engage with the oblique portions of the teeth for returning the bracket to its normal position, substantially as described.

2. An escapement for type-writing machines consisting of a space rack provided with teeth each having a straight and an oblique portion on its face, a bracket mounted to rock transversely to the space rack, a spring-pressed stepping-dog pivoted to said bracket to swing transversely to the plane of the faces of the teeth and adapted to engage the straight portions of the teeth, stops on either side of the stepping-dog for controlling the throw of the same, and a space-cam rigidly mounted on said bracket and provided with an oblique portion adapted to engage with the oblique portionsof the teeth for returning the bracket to its normal position, substantially as described.

3. An escapement for type-writing ma-v chines consisting of a space rack provided with teeth each having a straight and an oblique portion on its face, a bracket mounted to rock transversely to the space rack, a spring-pressed steppingedog pivoted to said bracket to swing transversely to the plane of the faces of the teeth and having its nose pivoted to the space-arm and adapted to engage the straight portions of the teeth, stops on either side of the stepping dog for controlling the throw of the same, and a space-cam rigidly mounted on said bracket and provided with an oblique portion adapted to engage with the oblique portion of the teeth for returning the bracket to its normal position, substantially as described. f

4. An escapement for type-writing machines consisting of a space rack provided with teeth each having a straight and an oblique portion, a rocker, a stepping-dog mounted on the rocker in position to engage the straight portions ofthe teeth and to swing parallel with the plane of the space-rack, and a space-cam attached to the rocker to move transversely to the space-rack and adapted to engage the oblique portions of the teeth thereof for returning the rocker to its normal position, substantially as described.

5. In a type-writing machine, the combination with the key and space-bar levers and with the carriage having an attached rack provided with teeth each having a straight and an oblique portion on its face, a rocker connected with the key and space-bar levers, a bracket rigidly mounted on said rockerand oscillating transversely to the space-rack, a

spring-pressed stepping-dog pivoted to said bracket to swing transversely to the plane of the faces of the teeth, stops on either side of the stepping-dog for controlling the throw of the same, and a space-cam rigidly mounted on said bracket and provided with an oblique portion adapted to engage with the oblique portions of the teeth for returning the bracket to its normal position, substantially as described.

In testimony whereof I have hereunto set my hand in the presence of two subscribing witnesses.

JAMES H. DYETT.

Witnesses:

EUGENIE P. HENDRICKSON, A. FABER DU FAUR, Jr. 

